Now, Crunch has taken the company’s RipSurfer X and designed a class that taps the board’s potential for both fun and fitness at the highest level yet.

Designed by the gym’s star instructors Marc Santa Maria and Zuta Gilchriest, who are both real-world surfers, Surfset & Sand is an interval class in which you alternate, with a partner, between sequences on the board and on the floor with a sandbag.

On the board, my core was rudely awakened as we moved through planks, squats, and balance exercises that required a new level of stabilization in order to not fall off.

On the floor, the sandbag was a more than adequate weight for toning arms, abs, and leg muscles throughout a variety of different moves—from squats with overhead presses and bent over rows, to moving our feet in and out in plank pose, with the sandbag acting as a sliding disc.

At the end of class, we put all of the moves together into a simulated surf sequence, paddling out on our stomachs, popping up as the wave approached, and rocking back and forth to the Beach Boys. Throughout, Santa Maria, who sports a surfer shag and wears board shorts, spurred us on by blowing a lifeguard whistle, and Gilchriest’s energy was huge and infectious.

It should be cheesy beyond belief, but its novel nature combined with the real challenge of the workout just makes you laugh with glee instead, so that during the hardest portions, you’ll barely notice how sweaty you’re getting. Coconut water would be the perfect follow-up. —Lisa Elaine Held

Who’s it for: Gym rats who are in a rut, Pilates lovers who want more cardio, surfers in the off-season